Azula the blue fire shooting super bitch. Whom you can't kill by throwing off a mountain and can shoot fire from her feet and fly on said fire. Vs ms. I like to kill soft cuddly parents and have to HIT my target directly near misses don't count.

Small room, fight starts, room explodes in fire, someones wand burns to ash followed by her hand, arm, rest of body.

I know this discussion was way in the past. But don't forget the fact that Bellatrix can apparate - if you take her sudden kill of Sirius from the film, she emerged and killed him before you were really aware that she was there.

Potentially she could appear from nowhere and kill Azula almost instantly; that doesn't seem to be Bellatrix's style however - she likes to face her opponents head on, and tease and taunt them before she kills them. As Dumbledore said: "...dear Bellatrix, who likes to play with her food before she eats it...".